Interferometric fiber-optic gyroscopes are increasingly used in medium to high performance inertial applications. For example, interferometric fiber-optic gyroscopes are used in inertial navigation applications, such as in military applications of a tactical nature (i.e., of short range, short time, and lower performance) and of a strategic nature (i.e., of long range, long time, and higher performance). Interferometric fiber-optic gyroscopes are also used in many commercial applications. As one example, a tactical-grade interferometric fiber-optic gyroscope is used to stabilize the yellow line projected on the ground during a televised football game to indicate the point that must be crossed by the offense to make a “first down.”
Interferometric fiber-optic gyroscopes typically use integrated-optic phase modulators to introduce a non-reciprocal phase shift to counter-propagating light beams to aid in the measurement of inertial rate. These phase modulators often exhibit linear low-frequency dynamics (i.e., a complex gain that varies as a function of frequency). Conventional implementations of interferometric fiber-optic gyroscopes typically do not, however, compensate for these linear modulator dynamics. As a result, the presence of the linear modulator dynamics often degrades the performance of the gyroscopes and causes errors.